Portable radio receiving set



Feb. 24, 1931.

F.'A. MAGEE' PORTABLE RADIQ RECEIVING SET Filed Nov. 30, 1926 2 Sheets-Sheet 1 INVENTOR. Frank/l. M0786.

A TTORNEY.

Feb. 24, W31. F. MAME PORTABLE RADIO RECEIVING SET Filed Nay. 50, 1925 2 Shams-Shem 2 INVENTOR. Pram/(A M0 A TTORNEY.

Patented Feb. 24,

eans UNITE "STATES PATENT OFFICE A. MAGEE, or omoiioo, ILLINOIS PORTABLERADIO RECEIVING SET Application filed November 30, 1926. Serial No. 151,773.

My invention relates to an improved construction of radioreceiving set .by whichthe entire apparatus involvedin receiving and" amphfymg the radio impulses, as well as the batteries required, a loudspeaker and a receiving loop, areall contained 1n a single cabinet or case of such sizeand total: weight that it may readily be carried to any desired location and used wherever desired toreproduceradio programs Without the necessity of adding anything to the set or attaching any outside wires-of any kind toit. p p

It will be understood that in-connection with receiving sets of the kind referred to, intended to be portable, it is of the utmost importance that the cabinet or case be of as small size and weight as possible, and at the same time it is necessary that the radio receiving set be of the multi-stage variety and constructed to amplifythe receivcd impulses effectively and without distortion, I find it desirable to employ five stages in the receiving set, two of them being radio frequency stages followed by a detector stage and this in turn followed by two stages of audio frequency. My invention pertains particularly to accomplishing the results set forth by several features of construction and aparticu lar arrangement of the parts resulting in a much reduced bulk of the outfit as a whole and a relatively small weight of the apparatus in its complete condition. These several features of improvement characterizing my invention will bestbe understood by ref;

erence to the accompanying drawings showing a preferred embodiment thereof in which Fig.1 shows my receiving set in back elevation in open condition, y Fig. 2 is a sectional view of the parts shown inFig. 1 taken along the line 2-2, with the covers in their closed positions,

"Fig. 8 shows in a view similar to Fig. 2 the front cover removed andthe receiving set drawn from the case for inspection or repair, Fig. 41s a front elevation of my receiving set with the front cover broken away to show a partial outside elevation and a partial elevation of the panel board and front inner wall of the case, Fig. 5 is a detail view to an enlarged scale showin the battery switch in front eleva tion anc a part of the front cover in place and broken away,

Fig. 6 is a vertical sectional view to an enlarged scale of the parts of the construction shown in Fig. 5, this view being taken along the line 6 -6 in Fig. at and Fig. 7 shows in front elevation to a reduced scale the front cover removed and in the relation it occupies to the case when the setis in use. a

Similar numerals refer to similar parts throughout the several views.

As shown in Figs. 1 and 2 my construction consists of a case 10 having a loud speaker 11 mounted again the top wallthereof and 00- cupying a part of the upper portion of the case, the speaker being connected with a re ceiver unit 12. Below the speaker 11, several cells 13 of dry battery are disposed on their sidesextending from back to front of the case, in which position they are supported by a horizontal partition 14 extending the full width of the case. The batteries 13 occupy but part of the space immediately above the partition 14: and in the remaining space, left by the batteries 13 and the speaker 11, two blocks of dry batteries 15 are supported by the partition 14, one upon the other, the size of the batteries15 being suchthat they substantially fill said remaining space. The batteries 13 are of the class commonly known as A batteries for the purpose of heating the filaments of the vacuum tubes and the batteries 15 are of the class commonly called B batteries for applying to the plates of the vacuum tubes the requisite voltages.

The receiving set consists of a control panel 16 and a sub-panel 17 secured together in 17 is in horizontal'position and slightly above nor to secure the, contemplated results in view ofthe particular hook-up used. The main wiring of theset is preferably in the space between the sub-panel 17 and the bottom of the case 10. Near the rear edge of the sub panel 17 bolts or screws 19 are secured to-the bottom wall of the'case and 'projectupw'ardly therefrom through the sub-panel 17 to hold v from thezspeaker to thehearen- To enclose it in place in the case, nuts 2Q-being employed to hold the sub-panel in spaced relation from the bottom of the case to clear the wiring on- 1 the sub-panel. The sub-panel '17 is preferably held in place on the bolts 19 by the thumb nuts 21 as indicated. As a result of the construction'just described, when it is de' sired to examine the apparatus carried by the panel 16 and the sub-panel 17, all that is necessary is to first remove'thefvacuum tubes from their sockets, and then to remove the 'thumb nuts 21, after which the sub-panel 17 may readily be lifted at its'rear edge from engagementwith the bolts 19, and the panel 16 and the sub-panel 17 may be moved bodily from the case as indicated in Fig. 3, this beingv permitted by the cable of conductors 22 con- 1 necting the apparatus with the batteries and loud speaker. f

The relation between the loud speaker, the batteries and the apparatus of the receiving set above described is important, as it effects a maximumseparation between the receiver unit 12 and the apparatus involved in the radio frequency stages, eliminating the com munication of microphonic noises from the unit 12 to the amplifying apparatus.

It will be understood that any desired hookup may be used in connection with the receiving set andithat'no claimis madefor any particular hook-up or arrangement of apparatus on the panel 16 andsub-panel17in the present application, for which reason the ap- V paratus and its connections are not speclfically describedherein.

It will be noted that the partition 14 does not extend to the rear surface of the case 10, but is cut away over the vacuum tubes 13.

This construction is employed to afford a clearance over the vacuum tubes so that they may be removed from their supportingsock ets and inserted therein, at the same time maintaining the distance between the bottom of the batteries and the bottom wall of the case at a minimum. ,W ere the shelf 14extended to therear edge of the case, the latter would necessarily be higher and more bulky, thus defeating in this rcgard,the desired condition of extreme compactness. I The back of the cas'e has hinged thereto a cover 23 which is held in closed position by suitable fastening devices, preferably snap catches, so that ready access may be had to the batteries and vacuum tubes for replacement purposes without disturbing any of the other parts of the apparatus and without re quiring the removal of the receiving set from v an opening 25 is formed immediately under the top-wall of the case 1O,th1sopen1ng beingin line with the delivery opening of the speaker 11 to permit the passage of sound Waves the frontof the case and the control knobs carried by the'panel 16, I provide a false front cover 26 extending from substantially the plane of the outer surface of the panel and front wall 2% of the case, and this front cover is provided with edge flanges 26a, forming a recess'in the'fcover ofasu'liicient depth to clear the control knobs on the panel 1 6. In

the said recess'l secure blocks 27 in'the cornersthereof, to support the'turns of wire 28 constituting the receiving loop of the set, the corner blocks being so placed that the loop wires lie along the inner surfaces of the flange pieces 26a of the front cover. In this manner 1 am able to give the loopwires an effective and efficient arrangement and'relati'on, at the same time entirely protectingthem from accidentalinjury; As indicated in Fig. 4, the front cover 26is hinged preferably at its lower edge asindicated at29, to the case 10, the hinges employed being preferably of the separable kind so that when the cover is swung to its open position, it may be removed from the case to permit its "use as a receiving loop. Fastening devices of any convenient kind, for example spring catches as indicated at 38, may be employed to hold the front cover26 in its closed condition. e

To protect the batteries 13 from being connected and subject to current drain when the case is closed, I locate a battery switch 30 in one of thelower corners 'of'the panel 16 and preferably employ a switch of the rotary kind,-having a short operating arm 30a. The

switch 30 is purposely so located on the panel 16, relatively tothe adjacent corner block 27 in the front cover 26, that when the switch is in its closed or on position, the'arm 30a extends into the path of the said corner block, the proportion of the parts being such that for this position of the switch, the front cover cannot be closed on account of the corner block 27 last referred to, striking the arin 30a. Withthe switch 30 in its open or ofiposition however, the arm 30a isin line with the clearance space between the adjacent corner block 27 and the adjacent corner of the front cover, so that'the said corner block is then free to move to the position it occupies when the front cover is closed and in this way a safeclip 31 to hold the connecting wires 28a of the loop, when the set is not in use, these connecting wires being preferably connected at their ends with small plugs 32. 'I also preferably secure to the inside of the front cover 26, a

. second spring clip 33 for holding within the cover a supporting post 34 having split ends as indicated to support the loop when in use. One of the end flange members 26a is provided with a socket 35 and the top of the case 10 is provided with a similar socket 36 to receive the endsof the post 34ztoholdthe loop in vertical position and at the same time permit free turning of it during the use of theset. The panel 16 is preferably provided with jacks 37 to receive the plugs 32 during the use of the set.

The case 10 is provided with a handle 39 to facilitate carrying-the set when desired.

As a result of my construction I am able to produce a complete portable radio receiving set including batteries, loud speaker and loop aerial in a case measuring over all when closed only eight and one half inches from front to rear, ten inches in height and twelve and one half inches in length and I am able to reduce the weight of the entire outfit to twenty four pounds. This result issecured using standard A batteries of the cylindrical kind measuring two and one half inches diameter and six and one half inches long each, and two standard volt B battery blocks each measuring two and a half inches by four and a quarter inches by six inches. The vacuum tubes employed are preferably of the kind known as four volt tubes using a very small filament current. These figures are mentioned specifically on account of important requisites of a portable radio receiving set being compactness and lightness. At the same time I am able to use as a part of the equipment a five tube receiving set and a speaker construction capable of delivering results comparing favorably with many stationary five tube receiving sets.

While I have shown my invention in the particular embodiments above described, it will be understood that I do not limit myself to this exact construction as I may employ equivalents known to the art at the time of the filing of this application without departing from the scope of the appended claims.

What I claim is:

1. In a portable self contained radio receiving set, the combination of a' casing, radio receiving and amplifying apparatus including aplurality of vacuum tubes in the bottom part of said casing, a loud speaker and receiver unit in the top part of said casing, a

shelf fixed in said casing, and batteries carred by said shelf between said receiver unit and said receiving and amplifying apparatus to effect a maximum separation of the former from the latter to eliminate mieroplionic noise. a i 1 a 2. In a portable self contained radio receiving set, thecombination of afcasingya radio receiving andamplifying apparatus in eluding a plurality of vacuum tubesin said casing, a vertical control panel across the front of said casing, a switch having a movable arm, a recessed cover for enclosing said panel, a block in the recess of said cover in line with said switch arm for the on position of said arm to prevent closing said cover for said on position and clearing said arm and switch for the off position of said arm, and a loop aerial in said cover recess and supported in part by said block.

3. A portable radio receiving set comprising a casing, a handle for said casing, a movable closure for the rear of said casing through which the apparatus within said casing is rendered accessible, a removable false front cover for the front of said casing, and means on said cover and the top of said casing whereby said cover is mountable for rotational movement on the top of said casing.

4. A portable radio receiving set comprising a casing having an inner front wall, a handle for said casing, a movable closure for the rear of said casing through which the apparatus within said casing is rendered accessible, a removable false front cover for the front of said casing having a loop antenna therein, and means whereby said cover is mountable for rotational movement 011 the top of said casing thereby to form an antenna frame adjustable to any horizontal direction without disturbing the casing,

5. A portable radio receiving set comprising a casing having an inner front wall, a handle for said casing, a movable closure for the rear of said casing through which the apparatus within said casing is rendered accessible, an apparatus carrier insertable into said casing from the front and having a front panel forming part of the front wall of said casing, a removable false front cover for the front of said casing, and means whereby said cover is mountable for rotational movement on said casing, said inner front wall having an opening therein above said front panel adapted to constitute the outlet for the sound waves issuing from within.

6. A portable container for radio receiving apparatus comprising a five sided casing, a movable closure for the rear of said casing, a false front cover for the front of said casing and means whereby said false front cover may be rota. ably mounted on said casing at a point spaced from the front thereof where free rotation of said cover is unobstructed by the casing, said false front cover having means for supporting a loop antenna therein.

4- f V V 7 1 ,794,025

7, A portable container for radiofreceiving apparatus comprising a'five sided casing, a a movable closure for the sixth side of said casing, a false cover for'one of said six sides,

- 5 said false, cover having means for supporting a loop antenna therein, andmeans Where- E V by said loop antenna maybe rotatably mount- I 7 ed on; said casing at the top thereof and spaced therefrom. v V v '1 In Witness whereofilhereunto subscribe my name this 26th day of November,'A.,D.

- FRANK A. MAGEE. 

